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1 天前 · Definition The Fourier transform is an analysis process, decomposing a complex-valued function () into its constituent frequencies and their amplitudes. The inverse process is synthesis, which recreates () from its transform.We can start with an analogy, the Fourier series, which analyzes () on a bounded interval [/, /], for some positive real number .
1 天前 · Principal component analysis (PCA) is a linear dimensionality reduction technique with applications in exploratory data analysis, visualization and data preprocessing. The data is linearly transformed onto a new coordinate system such that the directions (principal components) capturing the largest variation in the data can be easily identified.
3 天前 · In probability theory and statistics, a normal distribution or Gaussian distribution is a type of continuous probability distribution for a real-valued random variable.The general form of its probability density function is = ()The parameter is the mean or expectation of the distribution (and also its median and mode), while the parameter is its standard deviation.
2 天前 · Science is a rigorous, systematic endeavor that builds and organizes knowledge in the form of testable explanations and predictions about the world. Modern science is typically divided into three major branches: the natural sciences (e.g., physics, chemistry, and biology), which study the physical world; the social sciences (e.g., economics, psychology, and sociology), which study individuals ...
1 天前 · The port numbers in the range from 0 to 1023 (0 to 2 10 − 1) are the well-known ports or system ports. They are used by system processes that provide widely used types of network services. On Unix-like operating systems, a process must execute with superuser privileges to be able to bind a network socket to an IP address using one of the well-known ports.
5 天前 · In mathematics, the gamma function (represented by Γ, the capital letter gamma from the Greek alphabet) is one commonly used extension of the factorial function to complex numbers. The gamma function is defined for all complex numbers except the non-positive integers. For every positive integer n, Γ ( n ) = ( n − 1 ) ! . {\displaystyle ...
1 天前 · Sun. The Sun is the star at the center of the Solar System. It is a massive, nearly perfect sphere of hot plasma, [18] [19] heated to incandescence by nuclear fusion reactions in its core, radiating the energy from its surface mainly as visible light and infrared radiation with 10% at ultraviolet energies.
